Hi, some details - I've done two vacations in the past two years, it was a week each year (took lessons each time, for a few days), so I'm guessing I'm a beginner-intermidiate. I'm doing OK with most of the red ones.

In a month from now, I'm going to my third snowbaord vacation, in Val Thorens.
I'm wondering what's the best way to prepare myself, physically, and technically, so I'll be able to make the most out of the vacation, as I did'nt sonwboard for a year...

In general, I'm working out, so my physical shpae os OK. I plan to work out on the shin muscles, as it seems to me as a weak muscle of mine, and I suffered from it in the past vacations. Other than that, what can I do that will help my technique?
I thought about skateboarding, but I'm afraid that asphalt won't as forgiiving as the snow, and I might jepordize my vacation...So what other ways are there to strength my technique?

I plan to work out on the shin muscles, as it seems to me as a weak muscle of mine, and I suffered from it in the past vacations.

i have never experienced this. only thing i can think of is you are using the said muscle to engage your heel edge. i find it much easier to lean my calves against my highbacks
perhaps if you can adjust the forward lean of your highbacks you should do this.

The video Flylo posted is probably the best way to physically get ready.

Its silly but I see this a lot in lessons. People from low altitude come up to high altitude and think they can just rock as hard as us that live at 8,000'+ OR they ride like 3 days a season and think they can go straight to the big boy park and throw down, or huck 30 foot cliff drops into the deep powder... yeah.

As an instructor... yeah, I do recommend a tune up lesson, they are usually a ton of fun and you basically get a great guide and hopefully will learn some really awesome new techniques.

I'm not a doctor but I did stay at a Holiday Inn Express... seriously though... WATER, lots of it, HYDRATION is key to feeling well and not a ton of extra muscle fatigue. Also take aspirin if you can... again I'm not a doctor, so if aspirin makes you have heart attacks and shit then don't come cry to me because a snowboard instructor gave you medical advice. The aspirin helps thin your blood and helps the flow of oxygen through your blood stream at the higher altitudes.

Lastly, take it the fuck easy! Do you ride 100+ days a year?! No? OK then why are you trying to keep up with the locals? Just relax, take it easy and actually get some rest Apres Ski... in other words don't go to the bar and get lit and expect to not feel like shit riding the next day. Jump in the hot tub, get a good bite to eat and get some good sleep.